Apparatus for electrical uses



June 1, 1937. M. SVIKHART APPARATUS FOR ELECTRICAL USES Filed June 21, 19:54

INVENTOR M. L. SV/KHART ATTORNEY Patented June 1, 1937 UNITED STATES APPARATUS FOR Emcrmoar. USES Miles L. Svikhart, Garden City Park, N. "1., assignor to Western Electric Company, Incorporated, New York, N. York Application June 21,

2 Claims.

This invention relates to an electric switch and more particularly to an electrical switch having means to tiltably and removably retain in place therein a circuit making and breaking device 5 having a relatively frangible body.

An object of the invention is to provide a simple, rugged and reliable switch for securely and removably retaining in place therein in a tiltable cradle a tiltably operable circuit making and breaking device having a relatively delicate and frangible body.

With the above and other objects in view one embodiment of the invention contemplates a switch structure adaptable to be installed in a location within a ceiling or wall or floor member of a telephone boothor closet although it may be in any other appropriate site, and to be actuated by a push rod or othermember actuated by the opening and closing movements of a door, the switch in its preferred construction comprising a tiltable cradle having means thereon for securely and removably carrying a sealed glass tube having two fixed electrodes and a body of mercury therein.

Other objects and features of the invention will appear from the following detailed description of one embodiment thereof taken in connection with the accompanying drawing in which the same reference numerals are appended to identical 30 parts in the several figures and in which Fig. 1 is a broken view in perspective of an electric switch embodying the invention mounted on a. dome light assembly intended for use in a telephone booth, closet or the like and actuated 35 by an operating rod attached to one of the members of a door hinge;

Fig. 2 is an enlarged broken view in end eleva tion of the mercury tube cradle;

Fig. 3 is a similar view thereof in side elevation minus the push rod block; and

Fig. 4 is a detached, enlarged view in plan of the mercury switch tube.

In the embodiment of the invention herein disclosed, there is provided a generally rectangular cup like switch housing 20 mounted for convenience on the upper or rear side of the frame 2| of a dome light assembly intended to be installed in the ceiling of a telephone booth in such fashion 50 that the housing will be situated and concealed between the ceiling and the roof of the booth,

although the housing may also be placed in any convenient location.

A ring base 22 of insulating material is secured 55 to the floor of the housing 20 as by screws or bolts Y., a corporation of New 1934, Serial No. 731,583

23 passing through slots 24 in the base 22. An arcuate connection plate 25 is positioned on the ring 22 and secured thereto by rivets or screws 26. Contact clamp screws 21 and 28 are mounted in the plate 25. One conductor 29 of an electric current supply cable 30 is secured to the plate 25 by the screw 28. The other conductor 3| of the cable 30 is secured by a clamp screw 32 to a second contact plate 35 mounted on the ring 22, and provided with an inwardly extending tongue having a threaded perforation 34. The cable 30 brings electrical current from a source not shown. The plate 35 is also secured on the ring 22 by screws 26. The aperture 34 is connected to a conductor 38 leading to one terminal of a lamp socket of the usual type for holding an electric bulb or lamp not shown but which may be located under the dome like receptacle 40 which is part of the frame 2|.

The left hand end (Figure 1) of the plate 25 is, as best shown in Figure 2, bent to form a supporting lug 4| which carries a horizontal pivot pin 42 formed on a stud secured to the lug. A second supporting lug 43 is secured on the ring 22 by a screw 26 entering a horizontal foot 44 integral with the lug and a second pivot pin 45 is formed on a stud secured in the lug 43, the pin 45 facing the pin 42 and being coaxial with and spaced from the same.

The foot 44 has a radial inward extension provided with a threaded perforation 36 into which is secured a conductor 31 leading to the other terminal of the lamp concealed under the dome 40.

A mercury tube cradle generally indicated by the numeral comprising vertical side members 46 and 41 of resilient material, preferably spring metal such as brass or the like, and horizontal top and bottom members 48 and 49 of insulating material such as bakelite or the like, is pivotably supported on the pins 42 and 45 which enter appropriate perforations in the side members 46 and 41. The four members 46, 41, 48, and 49 are rigidly secured together by suitable means such as screws, bolts or rivets 5|. The side members have integral curved spring clamps 52 and 53 extending to the right and left respectively (Figure 3) to receive and hold a mercury switch tube of glass 54 embraced there-between. The clamps 53 are shown broken away for simplicity in Figure 2.

The mercury switch tube 54 of any suitable type is hermetically sealed and substantially evacuated of air, contains a liquid mass of metallic mercury 55 of appropriate volume and has two spaced parallel rod-like electrodes 56 and 51 sealed into the glass wall of one end of the tube. The clamps I! are formed to clasp and hold under gentle pressure the body of the tube 54. The clamps 83 are formed to press against the exterior ends of the electrodes 58 and 51 and may, if desired, be soldered thereto for better assurance of electrical contact therewith.

A short upstanding lever arm 8| of insulating material is rigidly secured to the outer face of the side member 41 of the cradle 50 by rivets II and a block 82 is pivotally mounted in the upper end of the lever arm 60 by means of an integral pin 03 Journalled in the arm. One end of an actuating rod BI is secured at right angles to the pin 03 in the block. The other end of the rod '4 is pivotally attached to a short lever arm I mounted on a shaft 06 rigidly attached to and rotated by the swinging leaf 61 of a hinge supporting a swinging part of the door 68 of the telephone booth, the otherleaf of the hinge being stationarily secured to the door frame not shown. The rod 84 is preferably threaded into the block 62 to permit of adjusting the angular relations oi the cradle 50 and the door 68.

In operation, the parts being disposed as shown in Figure 1 with the door of the booth open, the tube 54 is in the position shown in full lines in Figure 3 in which the gap between the electrodes ll and 51 is not closed by the mercury and consequently current from the supply cable 30 does not pass via conductors I! and 38 to the lamp concealed under dome 40. when the door is closed thus rotating the lever 05 in the direction of the arrow the push rod N tilts the cradle 50 into the position shown in dotted lines in Figure 3, the mercury flows down to the left hand end of the tube 54 (Figure 3) and bridges the gap between the electrodes II and 51 thus closing the lighting circuit and lighting the lamp. As an auxiliary feature, the contact plate 33 having a perforation I! is also mounted on the ring 22. A conductor 89 mounted in the perforation 39 is in contact with the same terminal of the concealed lamp as the conductor 31. Thus the conductor Q! is in effect connected to the conductor 31. A conductor Ill may be secured to the plate I! by a clamp screw H, and a conductor 12 may be secured to the plate 35 by the clamp screw II. The two conductors Hi and 12 may then be led to another lamp or fan or other electrical device and attached to the terminals thereof when such device will be connected in parallel with the first or principal lamp across the terminals BI and II and so will also be controlled by the mercury switch and hence by the door II. The apparatus of the invention thus provides simple, durable and reliable means for controlling a light and/or any other desired electrical device such as a fan for instance, associated with a telephone booth, closet or the like and actuated by a door.

The embodiment of the invention herein disclosed is illustrated merely and may be modified and departed from in many ways without departing from the spirit and scope of the invention as pointed out in and limited solely by the appended claims.

What is claimed is 1. In an electrical switch device comprising a tiltingly operable circuit making and breaking device having a relatively frangible hollow glass body and two metallic electrodes extending through a wall of the body, a cradle comprising a base of insulating materialpa pair of terminal members of metal mounted thereon, a pair of metal side members each tiltably mounted on one of the terminal members, each side member comprising a main portion and a body clamping member extending from the main portion in one direction and an electrode contacting member extending from the main portion in another direction, the two body clamping members being formed and disposed to receive and hold the frangible body therebetween and the two electrode contacting members being formed and disposed to each engage one of the electrodes.

2. In an electrical switch device comprising a tiltingly operable circuit making and breaking device having a relatively frangible cylindrical hollow glass body and two metallic electrodes extending through a wall of the body, a cradle comprising a base of insulating material, a pair of terminal members of metal mounted thereon, a pair of metal side members each tiltably mounted on one of the terminal members, each side member comprising a main portion and a body clamping member extending from the main portion in one direction and an electrode contacting member extending from the main portion in another direction, the two body clamping members being formed and disposed to receive and hold the frangible body therebetween under a relatively high degree of pressure and the two electrode contacting members being formed and disposed to each engage one of the electrodes under a relatively low degree of pressure.

MILES L. SVIKHART. 

